Switching power converters use a rectifier circuit in association with inductance (e.g., standalone inductor, or a winding of a transformer) to create a higher voltage (boost converter) or a lower voltage (buck converter) from a direct current (DC) source. In early power converters, and even today in lower efficiency power converters, the rectifier circuit is a diode acting as a rectifier. Voltage drop in the forward conduction mode of a diode can be relatively high (e.g., 0.7 to 1.0 Volts or more), thus making the overall efficiency of the power converter low. Power converter designers may attempt to increase efficiency by using a Schottky diode as the rectifier circuit, but even using Schottky diodes the overall efficiency of the power converter may not reach 90%.
When higher efficiency is desired, power converter designers may replace the diode with a standalone field effect transistor (FET) and a separate driver integrated circuit, thus creating a power converter with synchronous rectification. Use of a standalone FET and separate driver integrated increases the number of components on the bill of material (BOM) as well as the cost, and also increases the complexity of the underlying circuit board onto which the various components are mounted.